Do you actually see people diving with pony bottles?

[Dan]

Sure it is. I either stuff the 19cf pony in the carry on with my regs, computers, mask and lights or check it.

So, you have no problem removing the valve and regulator for TSA & custom inspections (making sure that you are not stuffing something dangerous/ illegal inside the bottle) every fricking time you fly, on top of additional weight you have to pay extra for when you fly to remote place, requiring limited baggage weight (for small airplane) and rigging up the oversize beer can back together before being filled back up with air? Tell that trick to @billt4sf as he has to do that often flying from San Francisco to Bali & to other remote places in Indonesia, like Raja Ampat.

 

[Dan]

That does NOT look like a 19 cf pony bottle.

13 cf at the most.

Well, I screen capture it from: XS Scuba Extra Air - 19 Cubic Feet Tank

 

[rek_diver]

So, you have no problem removing the valve and regulator for TSA & custom inspections (making sure that you are not stuffing something dangerous/ illegal inside the bottle) every fricking time you fly, on top of additional weight you have to pay extra for when you fly to remote place, requiring limited baggage weight (for small airplane) and rigging up the oversize beer can back together before being filled back up with air? Tell that trick to @billt4sf as he has to do that often flying from San Francisco to Bali & to other remote places in Indonesia, like Raja Ampat.

I don't have to remove the regulator from the pony because the regulator isn't on the pony, just like the regulator for the tank I will be renting isn't on the tank. Yes, the valve needs to be removed from the pony, a quick couple of twists and the valve is off. When I get to my destination I'll either stop somewhere and fill it or arrive early at the dive op and fill it before the dive, it takes all of 5 minutes. It doesn't really weigh all that much, I've never had an issue with overweight charges, it surely weighs a fraction of all my dive gear combined, it's just a few pounds.

Here's a 19cf pony bottle attached to an AL80 cylinder

 

[Dan]

So it sounds like some of us get a habit of sucking the pony bottle empty at the beginning of the dive & then start consuming the primary air source (AL80, HP100, etc.) afterwards.

 

[rek_diver]

Not me. The 3 or 4 times I've used my pony bottle as described earlier in this thread, when I realized I'd be using it I switched to it when I was down to around 1200 psi on the main tank, either used all of the gas or until it started breathing hard (I have no way to see what's in it at depth) and then switch back to my main tank.

 

[Dan]

I don't have to remove the regulator from the pony because the regulator isn't on the pony, just like the regulator for the tank I will be renting isn't on the tank. Yes, the valve needs to be removed from the pony, a quick couple of twists and the valve is off. When I get to my destination I'll either stop somewhere and fill it or arrive early at the dive op and fill it before the dive, it takes all of 5 minutes. It doesn't really weigh all that much, I've never had an issue with overweight charges, it surely weighs a fraction of all my dive gear combined, it's just a few pounds.

Here's a 19cf pony bottle attached to an AL80 cylinder

View attachment 430563

That looks indeed bigger than the one in XS Scuba.

Instead of the hassle of carrying the 19cf for your "stage" bottle (I stop using the word "pony" bottle, as I now understand how you are using it for) to extend your bottom time (right?), why not just renting the HP100, which gives extra 20cf over the AL80?

For the upcoming 13-day liveaboard trip to Indonesia, next month, 3 out of 13 of us are air hogs and we are able to get the boat to bring HP100 for them.

 

[MichaelMc]

In terms of how the *Air* is planned to be used:
Pony - Emergency air for you mostly. Mostly rec, as doubles/side provide redundancy already.
Deco - For deco, likely more enriched, like 50, 80, 100 O2.
Stage - More air for breathing on bottom, non emergency.
Bailout - Open circuit air to bail out of rebreather to if problems.

Not to say your could not carry an AL80, part of which you use as as stage air and the rest you keep as an emergency reserve, aka pony. But both in same bottle.

I could use a 19cf for deco or stage, or a HP100 just as a pony. It might be odd..., but nothing wrong with that, assuming I'm trained for deco/stage.

 

[rek_diver]

That looks indeed bigger than the one in XS Scuba.

Instead of the hassle of carrying the 19cf for your "stage" bottle (I stop using the word "pony" bottle, as I now understand how you are using it for) to extend your bottom time (right?), why not just renting the HP100, which gives extra 20cf over the AL80?

Who, me? I carry my 19cf pony bottle for emergency use, I used it only one time to extend a dive, that was in Roatan during a dolphin dive at 50'. When I switched from my primary tank to my pony bottle to give me some alone time with the dolphins as everyone else in the group started to run low on gas an ascend, I knew at that moment it was no longer usable as an emergency gas supply.

 

[Ayisha]

So it sounds like some of us get a habit of sucking the pony bottle empty at the beginning of the dive & then start consuming the primary air source (AL80, HP100, etc.) afterwards.

That would be a stage bottle, which in some agencies is partially used at the beginning of the dive or at a specified point in the dive.

 

[Ayisha]

...I switched to it when I was down to around 1200 psi on the main tank, either used all of the gas or until it started breathing hard (I have no way to see what's in it at depth) and then switch back to my main tank.

You could see what's in it at depth if you wanted to. When my pony was back-mounted, I had a pressure gauge on a long-ish hose clipped with a bolt snap to my left D-ring. When I switched to slinging it, I have the pressure gauge on a 6-inch hose tied in a typical way that it's kept where I can always see the pressure. Some people use a little button gauge.

It's good to be able to see the pressure of your pony/stage bottle in case it's leaking, since it is your emergency back up.